1. Field of the Invention
The present disclosure is directed to a semiconductor integrated circuit device and a method of fabricating the same, and more particularly to a semiconductor integrated circuit device that has an improved reliability and a method of fabricating the same.
2. Description of the Prior Art
With the increasing capacity and integration of semiconductor devices, high dielectric constant (high-k) thin films are being used as, for example, a gate insulating layer of a transistor, a dielectric layer of a capacitor, or a gate dielectric layer of a nonvolatile memory device. By using such high dielectric constant (high-k) thin films, leakage current occurring in the thin film can be sufficiently reduced as an equivalent oxide thickness (EOT) is maintained.
Using a high-k thin film, a metal oxide layer can be used as a dielectric layer of a capacitor. In this case, however, a part of a lower electrode may be oxidized in a process of manufacturing a dielectric metal oxide layer. If a part of the lower electrode is oxidized, the EOT of the dielectric layer is increased, causing deterioration of the device.